Brain organoids are powerful tools to decipher the cellular mechanisms involved during human brain development. Guguin et al. generated human cortical organoids to model the impact of a specific variant of the centrosomal RTTN gene to pinpoint cellular alterations leading to microcephaly in patients. This image shows a section of a cortical organoid, harvested at 46 days in vitro, that exhibits neuronal progenitors (magenta) organised into neural rosettes. Each rosette mimics a neural tube with highly proliferative neural progenitors lining the surface of the rosette lumen (delineated in yellow) that then differentiate radially into neurons (green). See Guguin et al. Download December’s cover page.

Image Credit: Justine Guguin